Can Brad Pitt’s bronzed biceps hold up a $200 million movie? “Troy” – the epic swords-and-sandals saga that features 1,500 extras, took over a year to make, and suffered injury, war and hurricanes during a world-spanning shoot – is really all about the Hollywood golden boy’s hot body.

“I remember our discussions early on,” says “Troy” director Wolfgang Petersen. “I said, ‘Brad, we all know that you do really like to hide that you are such a good-looking guy.

“Not here. The hair has to be nice and long and blond, and your body has to be pretty awesome.’ ”

His chiseled gluteus maximus gets plenty of screen time, too, in a number of raunchy love scenes.

Pitt hasn’t headlined a hit in this country since the 1995 thriller “Seven,” and nothing even approaching the scale of “Troy,” which opens Friday.

But there’s little doubt that the epic – which is rumored to have cost as much as quarter of a billion dollars – is being sold on the strength of his perfectly sculpted physique.

“He has the god-like beauty that Achilles needs,” says Petersen.

Pitt, who turned 40 in the final months of the shoot, welcomed the challenge of living up to that ideal. He quit smoking and launched into a grueling six-month exercise and diet regimen, during which he learned to sword fight and transformed his body into a muscle-bound combat machine.

“I wanted to see how far I could take it,” he says.

“I did what it takes, and it’s amazing, the body, how much it acclimates.”

“Troy,” loosely based on Homer’s poem, “The Iliad,” is the latest in a spate of historical sagas, and deals with epic themes of love, honor and revenge.

The production was similarly epic. Besides budget blow-outs and battle scars, tensions caused by the war in Iraq meant the set had to be moved from Morocco to Mexico, where the cast and crew endured 100-degree heat, stomach bugs and two hurricanes.

“Troy”tells the story of a protracted battle, sparked when Troy’s Prince Paris (Bloom) kidnaps the legendary beauty Helen (Kruger) from her husband Menelaus (Brendan Gleeson), the brother of Greek king Agamemnon (Brian Cox).

The Greeks lay siege to the city of Troy, but the elite Greek warrior Achilles mostly broods on the sidelines until his cousin is killed by Paris’ brother Hector (Bana), the eldest son of Troy’s king, Priam (Peter O’Toole.)

That’s when Achilles really unleashes his fury on the Trojans, showcasing his trademark move, which involves a kind of kung-fu leap and the plunge of a knife into his enemy’s neck.

Executing that move, incidentally, is how Pitt famously hurt his Achilles tendon in what he calls “a bad twist of irony.”

But that didn’t bother him nearly as much as a certain on-set Italian “hair guy” named Aldo.

“We called him Maestro – and he’s really, really good, but he would spend hours every morning on my hair, and I just got so tired of it,” says Pitt, now sporting close-cropped hair to film “Ocean’s Twelve,” the sequel to “Ocean’s Eleven,” with George Clooney.

Such attention to detail – hair, biceps, lats and abs – is not surprising.

Not since Bo Derek in “10” has a star’s body captivated the camera so thoroughly.

“There’s been a lot of emphasis on the physicality of the thing, but I just want to point out it’s what [actors] do,” says Pitt who, with his equally celebrated wife Jennifer Aniston, has just made it once again onto People magazine’s list of the world’s most beautiful.

“We change our hair, we change our clothes – whatever it takes to adapt the character, and this one required a great physicality.”

And it’s a lot of pressure on Pitt, who first came to audiences’ attention playing a hunky boy-toy in 1991’s “Thelma and Louise,” then played down his pretty-boy looks in films such as “Snatch” and “12 Monkeys.”

He says he’s not intimidated by having such a big-budget movie on his shoulders.

“I gotta tell you, going into it, I don’t see it any different from going into ‘Snatch,’ or ‘True Romance,’ which was just two days of work,” he says.

Pitt is currently filming “Mr. and Mrs. Smith” with Angelina Jolie and has just weathered a barrage of rumors that his marriage to Aniston, 35, is on the rocks.

“It’s funny that it comes out now, when the film’s coming out – it always has that kind of timing,” says Pitt, observing that the gossip is always about “making us better than we are, as Super-couple, or tearing us down for something.”

Aniston, whose long-running role on “Friends” finally came to an end last week, has made no secret of the fact she wants to have a baby, and Pitt says he’s “very much” looking forward to becoming a father.

“I’m really ready to take that on,” he says.

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A perfect 10

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